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Gravity and Nonconservative Force Model Tuning for the GEOSAT Follow-On SpacecraftThe US Navy's GEOSAT Follow-On spacecraft was launched on February 10, 1998 and the primary objective of the mission was to map the oceans using a radar altimeter. Three radar altimeter calibration campaigns have been conducted in 1999 and 2000. The spacecraft is tracked by satellite laser ranging (SLR) and Doppler beacons and a limited amount of data have been obtained from the Global Positioning Receiver (GPS) on board the satellite. Even with EGM96, the predicted radial orbit error due to gravity field mismodelling (to 70x70) remains high at 2.61 cm (compared to 0.88 cm for TOPEX). We report on the preliminary gravity model tuning for GFO using SLR, and altimeter crossover data. Preliminary solutions using SLR and GFO/GFO crossover data from CalVal campaigns I and II in June-August 1999, and January-February 2000 have reduced the predicted radial orbit error to 1.9 cm and further reduction will be possible when additional data are added to the solutions. The gravity model tuning has improved principally the low order m-daily terms and has reduced significantly the geographically correlated error present in this satellite orbit. In addition to gravity field mismodelling, the largest contributor to the orbit error is the non-conservative force mismodelling. We report on further nonconservative force model tuning results using available data from over one cycle in beta prime.
Document ID
20010106928
Document Type
Conference Paper
Authors
Lemoine, Frank G.
Zelensky, Nikita P.
Rowlands, David D.
Luthcke, Scott B.
Chinn, Douglas S.
Marr, Gregory C.
Smith, David E.
Date Acquired
August 20, 2013
Publication Date
January 1, 2000
Subject Category
Spacecraft Design, Testing and Performance
Meeting Information
American Geophysical Union 2000 Fall Meeting(San Francisco, CA)
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.